Production method for resin molding

Abstract

A production method for a resin molding includes: preparing fiber-reinforced resin by continuously feeding a long roving containing a reinforcing fiber, with its length unchanged, into base resin that has been heated to be plasticized; forming a resin molding using the fiber-reinforced resin; and heating the formed resin molding in a non-oxidizing atmosphere.

What is claimed is: 
     
         1 . A production method for a resin molding made of fiber-reinforced resin containing base resin and a reinforcing fiber, the production method comprising:
 a fiber-reinforced resin preparation step of preparing the fiber-reinforced resin by continuously feeding a long roving containing the reinforcing fiber, with its length unchanged, into the base resin that has been heated to be plasticized;   a resin molding formation step of forming the resin molding using the fiber-reinforced resin prepared; and   a resin molding heating step of heating, in a non-oxidizing atmosphere, the resin molding formed.   
     
     
         2 . The production method for a resin molding according to  claim 1 , wherein heating temperature for the resin molding is set at a temperature equal to or higher than a temperature at which reaction of a functional group at an end of the base resin occurs and lower than a melting point of the base resin. 
     
     
         3 . The production method for a resin molding according to  claim 1 , wherein the non-oxidizing atmosphere is at least one of a reduced-pressure atmosphere and an inert gas atmosphere. 
     
     
         4 . The production method for a resin molding according to  claim 1 , wherein, the fiber-reinforced resin preparation step and the resin molding formation step are continuously performed, the fiber-reinforced resin preparation step performed by using an injection molding machine including a plasticizing cylinder that heats and plasticizes the base resin while conveying the base resin in one direction and a feeding portion that continuously feeds the roving into the base resin being conveyed in the plasticizing cylinder and by using a mold connected to a tip of the plasticizing cylinder of the injection molding machine, and the resin molding formation step performed by charging the fiber-reinforced resin into a mold internal space of the mold. 
     
     
         5 . The production method for a resin molding according to  claim 4 , wherein into the base resin being conveyed in the plasticizing cylinder, a reaction aid having a function of assisting a functional group at an end of the base resin in reacting is fed from the feeding portion. 
     
     
         6 . The production method for a resin molding according to  claim 1 , wherein
 the fiber-reinforced resin preparation step is performed by, using an extruder including a plasticizing cylinder that heats and plasticizes the base resin while conveying the base resin in one direction, continuously feeding the roving together with the base resin into the plasticizing cylinder, and   the resin molding formation step is performed by, using an injection molding machine including a plasticizing cylinder that heats and plasticizes the fiber-reinforced resin while conveying the fiber-reinforced resin in one direction and a mold connected to a tip of the plasticizing cylinder of the injection molding machine, charging the fiber-reinforced resin prepared by the extruder into a mold internal space of the mold.   
     
     
         7 . The production method for a resin molding according to  claim 6 , wherein the extruder includes a feeding portion that continuously feeds the roving into the base resin being conveyed in the plasticizing cylinder. 
     
     
         8 . The production method for a resin molding according to  claim 6 , further comprising pelletizing the fiber-reinforced resin extruded from a tip of the plasticizing cylinder of the extruder and then feeding the fiber-reinforced resin pelletized into the injection molding machine.